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<TITLE>[Chapter 25] 25.54 java.lang.SecurityManager (JDK 1.0)</TITLE>
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<META NAME="date" CONTENT="Thu Jul 31 16:27:35 1997">
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<h2 CLASS=sect1><A CLASS="TITLE" NAME="JNUT2-CH-25-SECT-54">25.54 java.lang.SecurityManager (JDK 1.0)</A></h2>

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<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-25-SECT-54.1"></A></h3>
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<P CLASS=para>
This abstract class defines the methods necessary to
implement a security policy for the execution of
untrusted code. Before performing 
potentially sensitive operations, Java calls methods of the
<tt CLASS=literal>SecurityManager</tt> object currently in effect to
determine whether the operations are permitted. These methods
throw a <tt CLASS=literal>SecurityException</tt> if the operation is not
permitted.  

<P CLASS=para>
Normal applications do not need to use or subclass the
<tt CLASS=literal>SecurityManager</tt> class. It is typically only used
by Web browsers, applet viewers, and other programs that
need to run untrusted code in a controlled environment.

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<PRE>
public abstract class <tt CLASS=literal>SecurityManager</tt> extends Object {
    // <tt CLASS=literal>Protected Constructor</tt>
            protected <tt CLASS=literal>SecurityManager</tt>();
    // <tt CLASS=literal>Protected Instance Variables</tt>
            protected boolean <tt CLASS=literal>inCheck</tt>;
    // <tt CLASS=literal>Public Instance Methods</tt>
            public void <tt CLASS=literal>checkAccept</tt>(String <tt CLASS=literal>host</tt>, int <tt CLASS=literal>port</tt>);
            public void <tt CLASS=literal>checkAccess</tt>(Thread <tt CLASS=literal>g</tt>);
            public void <tt CLASS=literal>checkAccess</tt>(ThreadGroup <tt CLASS=literal>g</tt>);
        <b>1.1</b>public void <tt CLASS=literal>checkAwtEventQueueAccess</tt>();
            public void <tt CLASS=literal>checkConnect</tt>(String <tt CLASS=literal>host</tt>, int <tt CLASS=literal>port</tt>);
            public void <tt CLASS=literal>checkConnect</tt>(String <tt CLASS=literal>host</tt>, int <tt CLASS=literal>port</tt>, Object <tt CLASS=literal>context</tt>);
            public void <tt CLASS=literal>checkCreateClassLoader</tt>();
            public void <tt CLASS=literal>checkDelete</tt>(String <tt CLASS=literal>file</tt>);
            public void <tt CLASS=literal>checkExec</tt>(String <tt CLASS=literal>cmd</tt>);
            public void <tt CLASS=literal>checkExit</tt>(int <tt CLASS=literal>status</tt>);
            public void <tt CLASS=literal>checkLink</tt>(String <tt CLASS=literal>lib</tt>);
            public void <tt CLASS=literal>checkListen</tt>(int <tt CLASS=literal>port</tt>);
        <b>1.1</b>public void <tt CLASS=literal>checkMemberAccess</tt>(Class <tt CLASS=literal>clazz</tt>, int <tt CLASS=literal>which</tt>);
        <b>1.1</b>public void <tt CLASS=literal>checkMulticast</tt>(InetAddress <tt CLASS=literal>maddr</tt>);
        <b>1.1</b>public void <tt CLASS=literal>checkMulticast</tt>(InetAddress <tt CLASS=literal>maddr</tt>, byte <tt CLASS=literal>ttl</tt>);
            public void <tt CLASS=literal>checkPackageAccess</tt>(String <tt CLASS=literal>pkg</tt>);
            public void <tt CLASS=literal>checkPackageDefinition</tt>(String <tt CLASS=literal>pkg</tt>);
        <b>1.1</b>public void <tt CLASS=literal>checkPrintJobAccess</tt>();
            public void <tt CLASS=literal>checkPropertiesAccess</tt>();
            public void <tt CLASS=literal>checkPropertyAccess</tt>(String <tt CLASS=literal>key</tt>);
            public void <tt CLASS=literal>checkRead</tt>(FileDescriptor <tt CLASS=literal>fd</tt>);
            public void <tt CLASS=literal>checkRead</tt>(String <tt CLASS=literal>file</tt>);
            public void <tt CLASS=literal>checkRead</tt>(String <tt CLASS=literal>file</tt>, Object <tt CLASS=literal>context</tt>);
        <b>1.1</b>public void <tt CLASS=literal>checkSecurityAccess</tt>(String <tt CLASS=literal>action</tt>);
            public void <tt CLASS=literal>checkSetFactory</tt>();
        <b>1.1</b>public void <tt CLASS=literal>checkSystemClipboardAccess</tt>();
            public boolean <tt CLASS=literal>checkTopLevelWindow</tt>(Object <tt CLASS=literal>window</tt>);
            public void <tt CLASS=literal>checkWrite</tt>(FileDescriptor <tt CLASS=literal>fd</tt>);
            public void <tt CLASS=literal>checkWrite</tt>(String <tt CLASS=literal>file</tt>);
            public boolean <tt CLASS=literal>getInCheck</tt>();
            public Object <tt CLASS=literal>getSecurityContext</tt>();
        <b>1.1</b>public ThreadGroup <tt CLASS=literal>getThreadGroup</tt>();
    // <tt CLASS=literal>Protected Instance Methods</tt>
            protected native int <tt CLASS=literal>classDepth</tt>(String <tt CLASS=literal>name</tt>);
            protected native int <tt CLASS=literal>classLoaderDepth</tt>();
            protected native ClassLoader <tt CLASS=literal>currentClassLoader</tt>();
        <b>1.1</b>protected Class <tt CLASS=literal>currentLoadedClass</tt>();
            protected native Class[] <tt CLASS=literal>getClassContext</tt>();
            protected boolean <tt CLASS=literal>inClass</tt>(String <tt CLASS=literal>name</tt>);
            protected boolean <tt CLASS=literal>inClassLoader</tt>();
}
</PRE>
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<DIV CLASS=sect2>
<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-25-SECT-54.2">Passed To:</A></h3>

<P CLASS=para>
System.setSecurityManager()

</DIV>

<DIV CLASS=sect2>
<h3 CLASS=sect2><A CLASS="TITLE" NAME="JNUT2-CH-25-SECT-54.3">Returned By:</A></h3>

<P CLASS=para>
System.getSecurityManager()

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